Small Integrated Optical Head Device Using a Blue-Violet Laser Diode for Blu-ray Disc System

Abstract

We report the first integrated optical head device using a blue-violet laser diode (LD), which is a key device for realizing a small and thin Blu-ray Disc drive. While integrating seven optical elements and semiconductor chips into one device by adopting a molded optical element with high transmittance to the blue-violet wavelength, both small aberration and the small device size of 11 mm×6 mm×4.1 mm have been realized. We have also improved heat dissipation efficiency from this device to the base unit by adopting a newly developed package. At this time, we have implemented a performance evaluation of this small head device and have confirmed its good read/write performance as well as its adequate tolerances required for the Blu-ray Disc system.